This book explores how the continental philosophical tradition in the 20^th century attempted to understand madness as madness. It traces the paradoxical endeavour of reason attempting to understand madness without dissolving the inherent strangeness and otherness of madness. It provides a comprehensive overview of the contributions of phenomenology, critical theory, psychoanalysis, post-structuralism and anti-psychiatry to continental philosophy and psychiatry. The book outlines an intellectual tradition of psychiatry that is both fascinated by and withdraws from madness. Madness is a lure for philosophy in two senses; as both trap and provocation. It is a trap because this philosophical tradition constructs an otherness of madness so profound, that it condemns madness to silence. However, the idea of madness as another world is also a fertile provocation because it respects the non-identity of madness to reason. The book concludes with some critical reflections on the role of madness in contemporary philosophical thought.